cat > mysql-configmap.yaml << EOF
apiVersion: v1
kind: ConfigMap
metadata:
name: mysql
labels:
app: mysql
data:
master.cnf: |
# Apply this config only on the master.
[mysqld]
log-bin
slave.cnf: |
# Apply this config only on slaves.
[mysqld]
super-read-only
EOF
cat > mysql-services.yaml << EOF
apiVersion: v1
kind: Service
metadata:
name: mysql
labels:
app: mysql
spec:
ports:
- name: mysql
port: 3306
clusterIP: None
selector:
app: mysql
---
# Client service for connecting to any MySQL instance for reads.
# For writes, you must instead connect to the master: mysql-0.mysql.
apiVersion: v1
kind: Service
metadata:
name: mysql-read
labels:
app: mysql
spec:
ports:
- name: mysql
port: 3306
selector:
app: mysql
EOF
# 进入到pod mysql-0中，进行测试
kubectl exec -it mysql-0 bash
# 用mysql-client链接mysql-0
mysql -h mysql-0
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 276
Server version: 5.7.38-log MySQL Community Server (GPL)
Copyright (c) 2000, 2022, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql>
# 插入
mysql> insert into message value("hello chenby");
Query OK, 1 row affected (0.00 sec)
# 查看
mysql> select * from message;
+---------------+
| message |
+---------------+
| hello chenby |
+---------------+
1 row in set (0.00 sec)
mysql -h mysql-1.mysql
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 362
Server version: 5.7.38 MySQL Community Server (GPL)
Copyright (c) 2000, 2022, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql>
mysql>
# 查看数据库列表
mysql> show databases;
+------------------------+
| Database |
+------------------------+
| information_schema |
| cby |
| mysql |
| performance_schema |
| sys |
| test |
| xtrabackup_backupfiles |
+------------------------+
7 rows in set (0.01 sec)
# 使用cby库
mysql> use cby;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql>
# 查看表列表
mysql> show tables;
+---------------+
| Tables_in_cby |
+---------------+
| message |
+---------------+
1 row in set (0.00 sec)
# 查看message表结构
mysql> show create table message;
+---------+------------------------------------------------------------------------------------------------------+
| Table | Create Table |
+---------+------------------------------------------------------------------------------------------------------+
| message | CREATE TABLE `message` (
`message` varchar(50) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=latin1 |
+---------+------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)
mysql>
# 查询数据
mysql> select * from message;
+---------------+
| message |
+---------------+
| hello chenby |
+---------------+
1 row in set (0.00 sec)
mysql>
# 写入数据
mysql> insert into message values("hello world");
ERROR 1290 (HY000): The MySQL server is running with the --super-read-only option so it cannot execute this statement
mysql>
# 这是因为mysql-1是一个只读备库，无法进行写操作。